content: /* Copyright (C) 2016-2018 Alibaba Group Holding Limited
  
  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at
  
      http://www.apache.org/licenses/LICENSE-2.0
  
  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.
  ==============================================================================*/
  
  // Protocol Buffers - Google's data interchange format
  // Copyright 2008 Google Inc.  All rights reserved.
  // https://developers.google.com/protocol-buffers/
  //
  // Redistribution and use in source and binary forms, with or without
  // modification, are permitted provided that the following conditions are
  // met:
  //
  //     * Redistributions of source code must retain the above copyright
  // notice, this list of conditions and the following disclaimer.
  //     * Redistributions in binary form must reproduce the above
  // copyright notice, this list of conditions and the following disclaimer
  // in the documentation and/or other materials provided with the
  // distribution.
  //     * Neither the name of Google Inc. nor the names of its
  // contributors may be used to endorse or promote products derived from
  // this software without specific prior written permission.
  //
  // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  
  package com.google.protobuf;
  
  import static com.google.protobuf.Internal.checkNotNull;
  
  import com.google.protobuf.Internal.LongList;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.RandomAccess;
  
  /**
   * An implementation of {@link LongList} on top of a primitive array.
   *
   * @author dweis@google.com (Daniel Weis)
   */
  final class LongArrayList extends AbstractProtobufList<Long>
      implements LongList, RandomAccess, PrimitiveNonBoxingCollection {
  
    private static final LongArrayList EMPTY_LIST = new LongArrayList();
    static {
      EMPTY_LIST.makeImmutable();
    }
  
    public static LongArrayList emptyList() {
      return EMPTY_LIST;
    }
  
    /**
     * The backing store for the list.
     */
    private long[] array;
  
    /**
     * The size of the list distinct from the length of the array. That is, it is the number of
     * elements set in the list.
     */
    private int size;
  
    /**
     * Constructs a new mutable {@code LongArrayList} with default capacity.
     */
    LongArrayList() {
      this(new long[DEFAULT_CAPACITY], 0);
    }
  
    /**
     * Constructs a new mutable {@code LongArrayList}
     * containing the same elements as {@code other}.
     */
    private LongArrayList(long[] other, int size) {
      array = other;
      this.size = size;
    }
  
    @Override
    public boolean equals(Object o) {
      if (this == o) {
        return true;
      }
      if (!(o instanceof LongArrayList)) {
        return super.equals(o);
      }
      LongArrayList other = (LongArrayList) o;
      if (size != other.size) {
        return false;
      }
  
      final long[] arr = other.array;
      for (int i = 0; i < size; i++) {
        if (array[i] != arr[i]) {
          return false;
        }
      }
  
      return true;
    }
  
    @Override
    public int hashCode() {
      int result = 1;
      for (int i = 0; i < size; i++) {
        result = (31 * result) + Internal.hashLong(array[i]);
      }
      return result;
    }
  
    @Override
    public LongList mutableCopyWithCapacity(int capacity) {
      if (capacity < size) {
        throw new IllegalArgumentException();
      }
      return new LongArrayList(Arrays.copyOf(array, capacity), size);
    }
  
    @Override
    public Long get(int index) {
      return getLong(index);
    }
  
    @Override
    public long getLong(int index) {
      ensureIndexInRange(index);
      return array[index];
    }
  
    @Override
    public int size() {
      return size;
    }
  
    @Override
    public Long set(int index, Long element) {
      return setLong(index, element);
    }
  
    @Override
    public long setLong(int index, long element) {
      ensureIsMutable();
      ensureIndexInRange(index);
      long previousValue = array[index];
      array[index] = element;
      return previousValue;
    }
  
    @Override
    public void add(int index, Long element) {
      addLong(index, element);
    }
  
    /**
     * Like {@link #add(Long)} but more efficient in that it doesn't box the element.
     */
    @Override
    public void addLong(long element) {
      addLong(size, element);
    }
  
    /**
     * Like {@link #add(int, Long)} but more efficient in that it doesn't box the element.
     */
    private void addLong(int index, long element) {
      ensureIsMutable();
      if (index < 0 || index > size) {
        throw new IndexOutOfBoundsException(makeOutOfBoundsExceptionMessage(index));
      }
  
      if (size < array.length) {
        // Shift everything over to make room
        System.arraycopy(array, index, array, index + 1, size - index);
      } else {
        // Resize to 1.5x the size
        int length = ((size * 3) / 2) + 1;
        long[] newArray = new long[length];
  
        // Copy the first part directly
        System.arraycopy(array, 0, newArray, 0, index);
  
        // Copy the rest shifted over by one to make room
        System.arraycopy(array, index, newArray, index + 1, size - index);
        array = newArray;
      }
  
      array[index] = element;
      size++;
      modCount++;
    }
  
    @Override
    public boolean addAll(Collection<? extends Long> collection) {
      ensureIsMutable();
  
      checkNotNull(collection);
  
      // We specialize when adding another LongArrayList to avoid boxing elements.
      if (!(collection instanceof LongArrayList)) {
        return super.addAll(collection);
      }
  
      LongArrayList list = (LongArrayList) collection;
      if (list.size == 0) {
        return false;
      }
  
      int overflow = Integer.MAX_VALUE - size;
      if (overflow < list.size) {
        // We can't actually represent a list this large.
        throw new OutOfMemoryError();
      }
  
      int newSize = size + list.size;
      if (newSize > array.length) {
        array = Arrays.copyOf(array, newSize);
      }
  
      System.arraycopy(list.array, 0, array, size, list.size);
      size = newSize;
      modCount++;
      return true;
    }
  
    @Override
    public boolean remove(Object o) {
      ensureIsMutable();
      for (int i = 0; i < size; i++) {
        if (o.equals(array[i])) {
          System.arraycopy(array, i + 1, array, i, size - i);
          size--;
          modCount++;
          return true;
        }
      }
      return false;
    }
  
    @Override
    public Long remove(int index) {
      ensureIsMutable();
      ensureIndexInRange(index);
      long value = array[index];
      System.arraycopy(array, index + 1, array, index, size - index);
      size--;
      modCount++;
      return value;
    }
  
    /**
     * Ensures that the provided {@code index} is within the range of {@code [0, size]}. Throws an
     * {@link IndexOutOfBoundsException} if it is not.
     *
     * @param index the index to verify is in range
     */
    private void ensureIndexInRange(int index) {
      if (index < 0 || index >= size) {
        throw new IndexOutOfBoundsException(makeOutOfBoundsExceptionMessage(index));
      }
    }
  
    private String makeOutOfBoundsExceptionMessage(int index) {
      return "Index:" + index + ", Size:" + size;
    }
  }
  